Method of manufacturing an in-the-ear hearing aid

Abstract

In a method of manufacturing an in-the-ear hearing aid an auxiliary element, whose cross-section is larger than that of an auditory canal, is introduced into the auditory canal. As a result, the auditory canal is expanded. Subsequently, a hollow vent tube is inserted into the auditory canal, after which the auditory canal is filled with a viscous material. After the viscous material has solidified the mold is removed from the auditory canal. The vent tube insures that air is admitted to a space behind the mold. The mold thus formed has a cross-section larger than the cross-section of the auditory canal. Subsequently, a housing for the hearing aid is made, the mold being used as a template. Consequently, the heating aid will fit tightly in the auditory canal, which improves the wearing convenience. The auxiliary element used in this method has a cylindrical wall formed with a plurality of apertures to allow the passage of the viscous material to spaces between the auxiliary element and the wall of the auditory canal. The auxiliary element further comprises a sleeve for guiding the vent hose.

We claim: 
     
       1. A method of manufacturing an in-the-ear hearing aid to be worn in an auditory canal of a user and in proximity to a tympanic membrane, wherein the hearing aid comprises a first part which, when the hearing aid is present in an auditory canal, is situated near the tympanic membrane in a first part of the auditory canal, which first part of the auditory canal has a substantially non-deformable wall, and wherein the hearing aid comprises a second part which, when the hearing aid is present in the auditory canal, is situated near an auricle in a second part of the auditory canal, which second part of the auditory canal has an elastic wall, said method comprising: as a first step, making a mold of the auditory canal, then making a housing for the hearing aid using the mold as a template, and subsequently mounting components in the housing, the first step further comprising, filling the auditory canal with a viscous material in order to make the mold of the auditory canal, removing the mold from the auditory canal after solidification of said material, wherein, before the viscous material is introduced into the auditory canal, introducing an auxiliary element into the second part of the auditory canal so as to fit tightly therein, and wherein, when the auxiliary element is present in the second part of the auditory canal at the location of a cross-section of the auditory canal, the auxiliary element, taken perpendicularly to the longitudinal direction of the auditory canal, has at least one cross-sectional dimension thereof which is larger than a corresponding cross-sectional dimension of the second part of the auditory canal in the absence of the auxiliary element in the auditory canal. 
     
     
       2. A method as claimed in claim 1, further comprising: positioning a hollow vent tube having a flange at one end in the auditory canal with the flange near the tympanic membrane of the user before the viscous material is introduced into the auditory canal. 
     
     
       3. A method as claimed in claim 1, further comprising: applying a lubricant to the wall of the auditory canal before the auxiliary element is introduced into the auditory canal. 
     
     
       4. A method as claimed in claim 1, further comprising: introducing a user identifier into the viscous material after the auditory canal has been filed with said viscous material and before said material has solidified. 
     
     
       5. A method of making a mold for a housing of an in-the-ear hearing aid adapted to be positioned in proximity to a tympanic membrane in the auditory canal of a user of the hearing aid, said method comprising: introducing an auxiliary element into a part of the auditory canal which has an elastic wall, said auxiliary element having an approximately complementary shape to the wall of said part of the auditory canal and with at least one cross-sectional dimension of the auxiliary element being greater than a corresponding cross-sectional dimension of the elastic wall of said part of the auditory canal, said auxiliary element having apertures in a wall thereof and having a hollow vent tube extending through the auxiliary element and through an end of the auxiliary element adapted to face the tympanic membrane, said vent tube having a flange at a first end thereof near said end of the auxiliary element,   inserting said flange into the proximity of the tympanic membrane,   introducing a viscous material into the auditory canal through said auxiliary element and the apertures therein so as to fill a part of the auditory canal in the vicinity of the auxiliary element and up to the tympanic membrane,   allowing said viscous material to solidify, and   removing the auxiliary element and solidified mold from the auditory canal.   
     
     
       6. The method as claimed in claim 5 further comprising, prior to introducing the viscous material into the auditory canal, closing a second end of the vent tube to so as to form an air column within the vent tube such as to prevent ingress of viscous material into the vent tube via an opening in said first end thereof. 
     
     
       7. The method as claimed in claim 6 further comprising, after solidification of the viscous material and prior to removal of the auxiliary element and mold, opening said closed second end of the hollow vent tube.